Antialiasing Avatar Edges

Do you know who shot this photo?
Is it a late Hurrell?
If you know, pleasesend me mail
so I can properly credit it!

Prop edges are hard and jaggy. But avatars can have softer edges by
layering normal props over "ghost" props. The trick is to get the two props
to fit together nicely. The task is easily performed in Photoshop.
At left is a photo found on the net. We'll use it as the basis for
building a new avatar. We'll be using Photoshop 3.0 2.5 users can
get the same results, but using 3.0 layers makes it easier to bundle
the entire job into a single package (and PS 4.0 has the same functions).
The first step is to expand our grayscale values. The blacks in the
photo are really only about 20% gray, and gelled slightly red.
This gives the photo a great
hot-lamp look, but we need every bit of color depth we can scrounge
up, to get a good color-map image. So we expand the dynamic range
using (your choice)
"Adjust->Image->Levels..." or
"Adjust->Image->Curves..."

Next, we draw a transparency mask for the main photo layer. My own
preference is to use quickmask to build a selection, save the
selection, then copy that saved channel to
the layer's transparency mask. In this case, I
painted a general body-cutout mask in quickmask, then further trimmed
the transparency mask later by painting directly into the mask.
For precision, this prep work is done at the highest available
resolution
the original size. Downsizing to 44x44 or 132x132 size is only done
after the masks are done again, in the interest of eeking-out as much
picture data as we can, in the limited color space Palace provides
us.

If the original image has a very high-contrast edge, keep an eye
open for "freckles" when you downsize the image -- sometimes it
pays to paint-out the contrasting areas near a figure before
downsizing. That's not a problem for this image.

Once the masks are drawn and finalized, the picture is cropped tightly
around the mask and resized. I add two extra layers behind
the picture one layer, called "BG," is a clip from
one of the Palace rooms GIFs, to view the avatar pic in context
(Instead of a cutout, this can be a good place for Photoshop 4 users
to use "big data" and insert the enite room GIF...). The one shown
here is from Harry's bar. The second, which I called "way
back," is filled with our "greenscreen" value,
[R51G255B0] (This bright green
also conforms to the well-known web-safe color
set). The "way back" layer is only visible when
"BG" is hidden.
If that looks good, we select the front layer, containing our picture
("Foreground," "Layer 1," etc called "M" in the
illustration). We call "Duplicate Layer" (on the Layers
Palette) twice(Shortcut: drag the layer onto the page-turn
icon at the bottom of the palette). The new front layer we name
the "Hard" layer, the one behind it is the "Soft"
layer. We can now hide our original picture layer ("M").
Note that we're still in RGB mode, and we still have the whole picture
in both the "hard" and "soft" layers. We never
really cut these pictures out we let the transparency masks do the job for us.
That way, we can always change our minds.

Grayscale Mask versus 1-bit Masks, Visible
"Soft" Pixels

Hard Layer

Soft Layer

Actual Photoshop Edge

Ghost-Prop Edge

The next step is to threshold the transparency masks of the hard and
soft layers.
First select the hard-layer transparency mask. Use the "Image ->
Adjust -> Levels..." command to restrict it only to values about
174 (yes, this number did come out of thin air) or higher. In
other words, type "174 <tab> 1 <tab> 176
<tab>" and pinch the displayed values to black and
white.
Next, select the soft-layer transparency mask. We want it to contain
grayscale values from 64 to 174 less than 64 we want black, above 64 should be
white. Again, use "Levels..." to do the job, and hit
pbg2.gif "64 <tab> 1 <tab> 66 <tab>". The
"Soft" Image will be ever-so-slightly larger than the
"Hard" Image.
For preview purposes, we also want to set the transparency of
this "soft" layer to 50%. We should now have both layers set
correctly. As you can see, this isn't quite as good as a full
grayscale edge from Photoshop, but not bad and much cleaner than
normal jaggies. A little grace can go a long way.
Next we start making copies. We will want one copy each of
just the hard layer on the green background, and
just the soft layer on the green background. At the same
time, we'll convert to the Palace CLUT.

Make sure you've saved your work up to this point.

So for each of those layers, we show just what we need and hide all
other layers. Hit "Image->Duplicate..." and in each dup set the
visibility to only the "way bg" green plate and either the hard or
soft layers. All others hidden. Hit "Mode->Indexed Color"
("Image->Mode->Indexed..." in Photoshop 4) and convert to the Palace
CLUT (using "Custom" or "Previous." (This will
flatten the duplicate image, removing all the layers -- which is why
we do this with duplicates, not our "master" image). Dithering
is a matter of personal taste. Make sure that when you convert the
"Soft" layer, you restore its opacity to 100%
before doing the conversion.
Save each version, hard and soft. I usually strip off all extra
channels (leftover selections, etc) and save them as GIFs.

RGB Original

No Dithering

Dithered

Now we will start building our collection of props. For multi-prop
avatars, we tile both "soft" and "hard" images in
the usual way. Note that some 44x44 cells of the "Soft"
layer may be completely covered by the same area in the
"Hard" layer we can just skip or delete those
"soft" props, they'll never be seen. (In the example, no
ghosts are needed for the center cell, nor for the cell just to the
left of center).
The props in the "soft" layer need the "Ghost
Prop" attribute set under the "Prop Edit" menu.
Once all the props are pasted-in, properly offset, trimmed with the
eraser, and named, start building your avatar macro. Place all the
soft props first, then the hard ones on top. Save the entire
appearance as a macro, et voila!
You are anti-aliased.

Now the Bad News...

The current Palace software limits the number of props a character
can wear to nine. Quick addition will tell you that in the
example above, we need 16 props (two were unnessesary, remember?) for
the full anti-aliased 132x132 image. It's a big av. Under today's
Palace software, only the top (or bottom) two-thirds of the avatar can
be worn
and then user can carry no other props.
A more generous members' limit would be 20 props. That would let you
do almost any kind of prop layering trick and still have space for two
extra "dork" signs or handguns.